Yaf2, short for YY1-associated factor 2, is a protein-coding gene that modulates target gene transcription through epigenetic and non-epigenetic means. It is involved in various biological processes, such as apoptosis regulation, neural differentiation, and mitochondrial regulation [2,3,4]. It is also associated with the Polycomb repressive complex 1 (PRC1), which is crucial for epigenetic inheritance of cell identity [5]. Genetic models, like gene knockout mouse models, have been valuable in studying Yaf2's functions.

In neural differentiation of embryonic stem cells, Yaf2 knockout promotes neural differentiation, leads to redistribution of RYBP binding, increases enrichment of RYBP and H2AK119ub on cotargeted genes, and prevents ectopic derepression of non-neuroectoderm-associated genes. This shows Yaf2 has a distinct role in regulating neural differentiation compared to RYBP [1]. In zebrafish embryogenesis, depletion of Yaf2 using morpholinos activates apoptosis and causes developmental arrest, indicating its role as a survival factor during early development [4]. In human tumor cells, phosphorylated Yaf2 up-regulates FANK1 protein level by inhibiting its proteasomal degradation, and phosphorylated Yaf2 inhibits tumor cell apoptosis in a FANK1-dependent manner [2].

In summary, Yaf2 plays essential roles in multiple biological processes. Findings from gene knockout models have revealed its significance in neural development, embryogenesis, and tumor cell apoptosis. These insights into Yaf2's functions contribute to understanding the mechanisms of neural development, embryonic survival, and tumorigenesis, potentially providing new directions for related disease research and treatment.

References:

1. Liu, Yanjiang, Hu, Gongcheng, Yang, Shengxiong, Pan, Guangjin, Yao, Hongjie. 2023. Functional dissection of PRC1 subunits RYBP and YAF2 during neural differentiation of embryonic stem cells. In Nature communications, 14, 7164. doi:10.1038/s41467-023-42507-9. https://pubmed.ncbi.nlm.nih.gov/37935677/

2. Zhang, Shiqiang, Zhang, Xuan, Guan, Xin, Huang, Bingren, Chen, Deng. 2021. YAF2 exerts anti-apoptotic effect in human tumor cells in a FANK1- and phosphorylation-dependent manner. In Biochemical and biophysical research communications, 554, 99-106. doi:10.1016/j.bbrc.2021.03.105. https://pubmed.ncbi.nlm.nih.gov/33784512/

3. Kawamura, Kaz, Higuchi, Takuma, Fujiwara, Shigeki. 2021. YAF2-Mediated YY1-Sirtuin6 Interactions Responsible for Mitochondrial Downregulation in Aging Tunicates. In Molecular and cellular biology, 41, e0004721. doi:10.1128/MCB.00047-21. https://pubmed.ncbi.nlm.nih.gov/33875574/

4. Stanton, Sasha E, McReynolds, Lisa J, Evans, Todd, Schreiber-Agus, Nicole. 2006. Yaf2 inhibits caspase 8-mediated apoptosis and regulates cell survival during zebrafish embryogenesis. In The Journal of biological chemistry, 281, 28782-93. doi:. https://pubmed.ncbi.nlm.nih.gov/16891308/

5. Basu, Arindam, Wilkinson, Frank H, Colavita, Kristen, Fennelly, Colin, Atchison, Michael L. 2013. YY1 DNA binding and interaction with YAF2 is essential for Polycomb recruitment. In Nucleic acids research, 42, 2208-23. doi:10.1093/nar/gkt1187. https://pubmed.ncbi.nlm.nih.gov/24285299/